Eren does know various kinds of animals (though something like giraffe or okapi or even mountain lion he wouldn't recognise). Bears, sure. He knows what that is.

Polar bear, he imagines something that isn't really accurate. But it probably doesn't matter.

There is so much he never knew about the world he came from, and much more still he cannot imagine about other worlds.

He's not sure he understands entirely, but he'll accept smart bear. It's not the weirdest shit he's heard even in the last 24 hours, so what the hell. Why not.

"Why the hell would you wanna go to someplace no one but bears could live?" he asks.